Should CT be used for the diagnosis of RT-PCR-negative suspected COVID-19 patients?

The diagnosis of patients with Coronavirus disease 2019 (COVID-19) suspicion but negative reverse transcriptase-polymerase chain reaction (RT-PCR) test is challenging.

We aimed to investigate the diagnostic value of chest computed tomography (CT) in RT-PCR-negative patients with suspected COVID-19.

The study included patients who were admitted to our hospital with the suspicion of COVID-19 between 1 April 2020 and 30 April 2020 and tested negative after RT-PCR test, and underwent CT for further diagnosis. Initial CT findings were classified as typical, indeterminate, and atypical for COVID-19, and negative for pneumonia. Incidental findings on CT were noted.

Of the 338 patients with a mean age of 57 years (min 18 years-max 96 years), 168 (49.70%) were male and 170 (50.29%) were female. The most common symptoms were cough (58.87%), fever (40.82%), and dyspnea (39.34%). The CT findings were typical for COVID-19 in 109 (32.24%) patients, indeterminate in 47 (13.90%) patients, and atypical in 77 (22.78%) patients. The CT findings of 105 (31.06%) patients were negative for pneumonia. Incidental lung nodules suspicious of malignancy were identified in seven patients. Seventy-seven patients (22.78%) had extrapulmonary incidental findings CONCLUSION: The diagnostic value of CT in RT-PCR-negative patients with suspected COVID-19 is not very high. Based on clinical, laboratory, and chest x-ray findings, it may be more appropriate to refer patients to CT after the first triage, when necessary.